I may have found the answer to my question about using a FA bolt. It would seem that since the receiver itself has never been modified, it is too late now to alter it to allow use of the Uzi SMG bolt. At least that is the case if this post is considered to be factual.
http://www-2.cs.cmu.edu/afs/cs/user/wbardwel/public/nfalist/atf_letter46.txt
DEPARTMENT OF THE TREASURY
BUREAU OF ALCOHOL, TOBACCO AND FIREARMS
WASHINGTON, DC 20226
OCT -1 1998 F:FPD:FTB:GKD
3311
Dear Mr. :
This refers to your letter of July 21, 1998, requesting
information on permissible modifications to Uzi firearms that
have been converted to machineguns and registered in the National
Firearms Registration and Transfer Record (NFRTR). Your
questions will be answered in the order received in the letter.
1. If an Uzi type firearm was registered as a machinegun and
the conversion involved making a bolt to fit in the
semiautomatic receiver, with no modifications to the
receiver, can the receiver be legally modified now, so that
the standard factory Uzi machinegun parts may be used? What
if the bolt made to fit the semiautomatic type receiver is
destroyed as part of modifying the receiver to accept a
standard machinegun bolt?
Destruction of the registered Uzi conversion bolt would not allow
modifications to the semiautomatic Uzi receiver to allow it to
accept an Uzi machinegun type bolt. The alterations to the
receiver necessary to accomplish installation of an Uzi
machinegun bolt would result in the making of a machinegun, as
the altered receiver would be a machinegun configuration frame or
receiver. It is unlawful for anyone to make a machinegun except
as provided in 18 U.S.C. section 922(o).
2. If an Uzi semiautomatic carbine is converted into a
machinegun with a slotted conversion bolt which is itself
registered as a machinegun, may other remaining features of
the semiautomatic firearm be removed? In particular;
(a) May the barrel retaining ring, an integral part of the
feed ramp in the semiautomatic Uzi carbine, be removed?
- 2 -
Mr.
(b) May the barrel trunnion be bored out so that the gun
will accept unmodified Uzi machinegun barrels?
(c) May the sear openings in the bottom of the receiver be
enlarged up to permit the use of a full automatic style
sear?
(d) May the model name (only) of the semiautomatic carbine
marked on the left side of the receiver be removed and
replaced with a more appropriate marking for an Uzi
machinegun?
The alterations described above as (a), (b), and (c), done to a
semiautomatic configuration Uzi carbine receiver, would not be
prohibited, as they do not convert the semiautomatic receiver
into the configuration of a machinegun frame or receiver.
With reference to altering the markings, as described in (d),
this would be permissible provided that no markings are removed,
altered or obliterated that would result in a violation of Title
18 United States Code (U.S.C.), Chapter 44, section 922(k) or
Title 26 U.S.C., Chapter 53, section 5861(g).
We trust that the foregoing has been responsive to your inquiry.
If we can be of further assistance, please contact us.
Sincerely, yours,
[signed]
Edward M. Owen, Jr.
Chief, Firearms Technology Branch
